5/24/2016  |   10:30 - 10:45   |  302-303

USE OF GAME CAMERAS TO MONITOR FLOW IN SMALL, HIGH-GRADIENT STREAMS IN THE WHITE MOUNTAINS NATIONAL FOREST, MAINE AND NEW HAMPSHIRE, U.S.A. It is well known that disturbance caused by high discharge events can influence community structure of macroinvertebrates in streams. Unfortunately, logistical and financial constraints can make it difficult to continuously monitor flow in situ and generate storm hydrographs. The primary objective of this research was to explore the use of game cameras to monitor flow in small streams. Game cameras were installed overlooking sites on four streams and set to capture images hourly during daylight hours. Additional data collected at each site, as well as measured discharge, were used to estimate discharge using the slope-area method. Between mid-August and early November, the cameras recorded four events where discharge increased significantly above baseflow levels (e.g., Burnt Mill Brook, September event, Q = 0.48 m³ s^-1 to 13.81 m3 s-1 in 5 hours). All events were also very short-lived; return to near baseflow conditions occurred in less than 24 hours. As memory and cameras are cheap, and image quality is good, game cameras might be very useful to remotely monitor many aspects of stream ecology, especially at less accessible sites.

Brian Shelley (Primary Presenter/Author), Saint Joseph's College, bshelley@sjcme.edu;


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5/24/2016  |   10:45 - 11:00   |  302-303

EFFECTS OF DROUGHT AND DELUGE ON WATERBODIES IN LEON COUNTY FLORIDA Leon County Florida has recently emerged from a 14 year drought cycle, but area waterbodies are still experiencing residual drought effects. While low water levels can cause a decline in plants and wildlife, periodic dry spells can benefit the health of a lake by allowing sediment oxidation. However, water quality can decline as the concentration of pollutants increases when water evaporates and becomes stagnant. As a counterbalance, pollutants associated with stormwater runoff are not an issue during drought events, so an urban stream’s baseflow may be less polluted during a drought than during normal rainfall patterns. During periods of excessive rainfall, urban watersheds tend to have more runoff than forested areas since their impervious surfaces of pavement, roofs, and concrete, shed water quickly. Conversely, forested or grassy areas allow water to naturally soak into the ground. During my presentation, I will provide a case study explaining the importance of relating recent climate events, including drought, rainfall and runoff generation to water chemistry results and overall lake health.

Johnny Richardson (Primary Presenter/Author), Leon County, Florida, richardsonjo@leoncountyfl.gov;


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5/24/2016  |   11:00 - 11:15   |  302-303

FLOW REGIME AND INVERTEBRATE COMMUNITY RESPONSE ACROSS JAPANESE RIVERS Flow regime is thought to be a major driver of biodiversity and ecosystem integrity, but less is known about the response of stream invertebrates to flow. Our objective was to identify flow regime characteristics across Japanese rivers and its effect on stream invertebrates. We used long -term flow records from 418 gauging sites to quantify 122 hydrologic indices. A principal component analysis reduced the dimensionality of the data to 6 principal components. Generalized linear models (GLMs) revealed that topographic, climatic, geographic and anthropogenic (land use and large dams) factors were important determinants of flow regime. Data from 285 sites of the National Census on River Environments were used to investigate relationships between invertebrate communities and flow regimes. GLMs using principal components as explanatory variables revealed that magnitude, frequency and duration in flood and duration and rate of change in low flow were important determinants of invertebrate taxon richness. Our results can contribute to a better understanding of the effects of flow regime on the distribution of stream invertebrates and the maintenance of healthy stream ecosystems.

Yo Miyake (Primary Presenter/Author), Ehime University, miyake@cee.ehime-u.ac.jp;


Kento Yoshimura ( Co-Presenter/Co-Author), Ehime University, yoshimura.kento.09@cee.ehime-u.ac.jp;


Yuya Watanabe ( Co-Presenter/Co-Author), Fujita Construction Consultant, yuya-watanabe@fujitacc.co.jp;


Terutaka Mori ( Co-Presenter/Co-Author), University of Tokyo, moriterutaka@gmail.com;


Takumi Akasaka ( Co-Presenter/Co-Author), Obihiro University of Agriculture and Veterinary Medicine, t.akasaka@obihiro.ac.jp;


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5/24/2016  |   11:15 - 11:30   |  302-303

THE ROLE OF CONTEXT DEPENDENCY IN UNDERSTANDING THE EFFECTS OF LOW FLOW EVENTS ON FISH The natural hydrology of streams and rivers has been extensively altered due to dam construction, water diversion, and climate change. An increased frequency of low flow events will affect fish due to shifts in habitat availability, resource availability, and reproductive cues. I reviewed the literature to characterize the approaches taken to assess low flow events and fish, the main effects of low flow events on fish, and the associated mechanistic drivers. Most studies are focused on temperate streams and are comparative in nature. Lowered streamflow is associated with decreased survival, growth, and abundance of fish populations, and shifts in community composition, but there is considerable variation in effects. This variability in effects is likely due to context dependency. I propose three main sources of context dependency that drive variation in fish responses to low flow events: attributes of the low flow event, attributes of the habitat, and attributes of the fish. Awareness of these sources of context dependency can help managers interpret and explain data, predict vulnerability of fish communities, and prioritize appropriate management actions.

Annika Walters (Primary Presenter/Author), USGS Wyoming Coop Fish and Wildlife Unit, annika.walters@uwyo.edu;


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5/24/2016  |   11:30 - 11:45   |  302-303

TEMPORAL PATTERNS OF MACROINVERTEBRATE COMMUNITY STRUCTURE THROUGH RECORD FLOODING AND DROUGHT IN A FRAGMENTED RIVER Ecological responses to hydrologic alterations and river restorations are not well studied due to lack of monitoring after most projects. The Cache River in southern Illinois is divided into the upper Cache River (UCR), which suffers from erosion and channel incision, and the lower Cache River (LCR), which is impaired by reduced flow, sedimentation, and hypoxia. We examined macroinvertebrate community structure in this altered system during four summers with conditions ranging from record flooding to extreme drought. The UCR had higher invertebrate body size (p=0.03), higher diversity (p=0.02), and lower Hilsenhoff Biotic Index scores (p<0.0001) than the LCR. Body size was highest in the flood year (p=0.0005) in both river segments. The LCR had proportionally more multivoltine and fewer univoltine taxa than the UCR (p<0.0001). High spatial variation and a more tolerant community in the LCR precluded significant temporal patterns in the biomass of many individual taxa, as observed in the UCR. This study improves our understanding of the impacts of hydrologic alteration on communities and suggests proposed flow restoration in the Cache and similar systems could enhance ecosystem integrity.

Karen Baumann (Primary Presenter/Author), Murray State University, kbaumann1@murraystate.edu;


Eric Scholl ( Co-Presenter/Co-Author), U.S. Geological Survey, escholl@usgs.gov;


Heidi Rantala ( Co-Presenter/Co-Author), Southern Illinois University, hrantala74@gmail.com;


Matt Whiles ( Co-Presenter/Co-Author), University of Florida, mwhiles@ufl.edu;


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5/24/2016  |   11:45 - 12:00   |  302-303

UNTANGLING THE DIRECT AND INDIRECT EFFECTS OF DISTURBANCE ON CONSUMER COMMUNITIES IN AN ARCTIC RIVER Disturbance is a central determinant of patterns and processes in many ecosystems. Climate change is expected to increase the relative role disturbance plays in structuring communities. Arctic ecosystems are particularly susceptible to changing disturbance regimes where rapidly warming temperatures are degrading permafrost and altering the magnitude and timing of river flows. Our study documented decadal-scale changes in algal availability and invertebrate assemblage structure and productivity as related to disturbance patterns. Invertebrate community productivity (range= 1986-6494 mgDM m-2 Y-1) closely tracked algal availability (range= 0.10-0.58 µg cm-2) while community composition was principally influenced by a series of floods. Our data suggest hydrologic regime mediates invertebrate community structure and productivity directly through scour and indirectly through the ‘legacy effect’ of increasing flows in any given year leading to decreased algal availability in the succeeding year. Species-specific responses demonstrate increases in epilithic algae can lead to increased production of mayflies, while competitive interactions may prevent strong responses from otherwise dominant blackflies. These results provide insight into how hydrologic regime can mediate resource availability and control aquatic invertebrate communities in the arctic.

Michael Kendrick (Primary Presenter/Author), The University of Alabama, kendrickmr@gmail.com;


Alexander D. Huryn ( Co-Presenter/Co-Author), The University of Alabama, huryn@ua.edu;


Anne Hershey ( Co-Presenter/Co-Author), The University of North Carolina at Greensboro, aehershe@uncg.edu;


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